Method of treating baseball bats, golf clubs, etc



July 15, 1930.

H. c. HANNA METHOD OF TREATING BASEBALL BATS, GOLF CLUBS, ETC

Filed Oct. 17. 1928 2 Sheets-Sheet l Jnren for,

m Paw ATTORNEYS H. c. HANNA July 15, 1930.

METHOD OF TREATING BASEBALL BATS, GOLF CLUBS, ETC

Filed Oct. 17. 1928 2 Sheets-Sheet 2 .[nrcnf'ozy a'M' WM' ATIORNEYJ Patented tip 35, 193

HENRY CLAY HANNA, F ATHENS, GEORGIA G BASEBALL BATS, GOLF CLUBS, ETC.

Application filed October 17, 1928. Serial No. 313,091.

This invention relates to the treatment of baseball bats and similar instruments provided with a hand-grip portion and an impact zone, and particularly to a method of treating such implements whereby the grip portion of the resultant product retains its natural inherent resiliency, and the impact portion is rendered more durable by an operation which includes the step of binding together the component layers of such portion.

The object of the invention is the provision of methods and means for so treating such an implement that all the advantages of the resiliency in the handle, and in the core of the impact portion are retained, while the adj acent outer layers of the impact portion are tightly bound together to eliminate separation of one layer from another, thereby rendering the implement more durable.

While the following specification discloses the invention as applied in the production of a baseball bat made of wood, it will be obvious that the application thereof is not so restricted, and that implements adapted for other purposes, and composed of material other than wood, may be advantageously so treated.

Other objects of the invention will be made to apparent in the following specification, when read in connection with the drawings forming a part of this application.

In the said drawings:

Fig. 1 is a side elevation of an installation adapted to treat the bats in accordance with my invention.

Fig. 2 is aside view, partly in vertical sec-- tion, showing a portion of the bat treating mechanism.

Fig. 3 is a view in cross-section taken longitudinally through a bat treated 'by my method, and,

Fig. 4 is a view in cross-section taken laterally through a bat.

Now referrin specifically to the drawings, in which like re erence numerals indicate like parts throughout the several views, 1 is a supporting rame, upon which is mounted a motor 2, having a drive shaft 3, geared to a pulley 4, having a hub 5, the pulley 4 being also geared to a drive wheel 6, of a compressor 7 Below the motor 2 is a pressure tank 8, and'a vacuum tank 9, pipes 10 and 11 respectively connecting the tanks 8 and 9 to the compressor 7, the compressor being so designed that, in operation by the motor, it maintains a vacuum in the tank 9, and a high pressure of air in the tank 8, as will be clearly understood. The top portions of the pipes 10 and 11 are provided with suitable valves 12 and 13 to control the air currents passable therethrough.

On each side of the compressor 7 is mounted a battery of retorts 14, adapted to receive the bats 15 for treatment. In Fig. 1 only four retorts are illustrated, but it is of course understood that the installation may be enlarged at will. Each retort 14, as best illustrated in Fig. 2, preferably comprises a metallic, vertically-extending air-tight cylinder, provided with a removable head 16, held in position by bolts 17 and nuts 18. The retorts are slightly longer than the bat billets 15, and are of a diameter such that 12 to 15 bats may be placed on end therein and out of contact each to each. In the formation of the bat billets, an outwardly-tapering, flat-faced knob 19 is produced centrally on the extreme outer end of the impact portion of the bat 15, and the latter are supportedin vertical position by said knobs, the fiat floor of the fluid-tight bottom 20, being adapted to this purpose.

Rising from the tanks 8 and 9, are pipes 21 and 22 respectively, pipe 21 being in constant communication with laterally-extendmg pipe 23, running alongside each of the retorts 14, and pipe 22 being in constant communication with a similarl directed pipe 24 extending adjacent each 0 said retorts. As best illustrated in Fig. 2, a take-off branch 25 connects the pipe 24 to an inlet 26 pro- Jecting into the top of each of the retorts,

a valve 27 controlling the flow of air through said inlet; similarly, a take-ofl' branch 28 connects the pipe 23, by way of the valve 29, to the inlet 26, it being evident from the foregoing that by manipulation of the valve 27, a vacuum may be induced within the retort, or that pressure may be applied therein, by manipulation of the valve 29.

A mixing tank 30 is mounted on the frame 1, preferably adjacent the motor 2, and is provided with a drive wheel 31, belted to the pulley 4, as illustrated in Figs. 1 and 2. The tank 30 is cylindrical in formation and is adapted to contain the material used in the treatment of the bats 15. Carried on the hub 32 of the wheel 31, is a bevel gear 33, in mesh with a similar gear 34, mounted on the top end of a shaft 35, extending centrally within the tank 30, and having a bearing slot 36 for its lower end. Two or more stirrer blades 37 are mounted on the shaft 35, for the purpose of agitating the mixture in the tank 30, preparatory 'to the introduction of the mixture into the retort 14, and baflie plates 38 extend inwardly from the sides of the tank, said plates tending to prevent a spiral formation within the tank under the rotation of the stirrer blades 37. The top of the tank is provided with a movable cover, not herein shown, to permit removal of a portion of the contents which is to be poured into the retorts 14, as desired. Or the tank may be in direct communication with each of the retorts by means of valve-controlled pipes, connected to the retorts exactly as are the tanks 8 and 9, in Which case the tank would be elevated above the retorts for gravity flow, and a sight gage be applied to each retort to indicate the height of the treatment liquid therein.

The principal constituent of the mixture prepared in the mixing tank, for subsequently treating the bats, is a powerful adhesive carried by or dissolved in water or other suitable vehicle. Since the main reason for deterioration of baseball bats is the tendency of the growth layers of the wood to become separated under hard usage, it is my purpose to so impregnate the bats with an adhesive that the said layers will be firmly bound together, thereby preventing the tendency of the ball striking portion of the bat to chip or split under impact. There are many classes of adhesives which might be used with some advantage, such as pyroxylin cement, mucilage or shellac, but most of them are either too weak for satisfactory results,

or so costly as to be prohibitively expensive as a commercial proposition. I have found by experimentation that casein glue is the most practicable adhesive for the purpose intended, because it readily dissolves in cold water and the mixture so formed is exceedingly strong when set. Unlike some other glues, such as animal glue, a. mixture of casein glue and water not only forms a perfect contact with the wood layers to firmly bind them together, but also leaves a minimum discoloration of the bats after the treat-' ment. In addition, the use of casein glue causes a minimum swell of the wood under treatment, and is thoroughly waterproof when set. The amount of casein glue dissolved in a given volume of water in forming the mix, may be varied to suit the circumstances, and dependent upon the porosity of the wood of which the bats are composed, and the tendency of the layer growths towards separation.

In treating the bat billets, the mix is constantly stirred by the blades 37 so that it is always in condition for supplying the hermetically-sealed retort 14. With said retorts containing the partially or completely formed bats to be treated, the handle portion of the bats extending upwardly, the bats held against flotation by the heavy plate 15, and the top 16 applied in position to hermetically seal the retort, the valve 27 is turned to place the interior of the retort in communication with the vacuum tank 9, through pipe 24, whereupon the sub-atmospheric pressure in said tank tends to induce a vacuum in the retort and to thereby withdraw air and moisture from the pores of the wood. The vacuumizing process is continued for the requisite time, and the valve 27 is closed, the mix being then inserted. into the retort and permitted to extend upwardly to the juncture of the handle portion and throat of the bat, as illustrated in Fig. 2, or to completely cover the billet, if treating a wooden implement which should be impregnated throughout its full length. If desired the mixture may be placed in the retorts before the creation of the vacuum.

At this stage of the treatment the valve 29 is opened slowly to admit gradually increasing pressure into the retort from the tank 8. This pressure is allowed to reach about 200 lbs. per square inch, and is continued for approximately one hour more or less, dependent upon the 'fluidity of the mix and the porosity of the wood. It is not necessary for the mix to penetrate deeply into the center of the wood, it being sufficient if the surface layers are firmly bound together. After the desired penetration has been attained, the pressure in the retort is gradually reduced to atmospheric, the retort is opened and the billets removed and placed in a drier. When properly dried the cells or pores of the wood are coated or filled with a very tough fihn which causes each layer of the wood to firmly adhere to the adjacent layer, thereby practically eliminating all probability of chipping or splitting of the outer surface of the impact portion of the bat. The mixture is drained from the re-' torts through the valve 40 and from the tank 30, through the valve 41.

In Figs. 3 and 4 is disclosed the degree of penetration desired, it being understood that the shaded portions 39 indicate the extent of penetration towards the center of the bil let. It will therefore be observed that none of the natural resiliency of the handle portion and core of the bat has been destroyed,

and that the outer layers of the barrel of the bat have been firmly cemented each to each, not only eliminating the liability of chipping or splitting under hard usa e, but also forming a thorough waterproo coating for the barrel of the bat, and thereby increasing its durability.

Various modifications of the invention hereindescribed may be suggested to those skilled in the art, but my invention covers all embodiments falling fairly within the scope of the appended claims.

I claim v 1. The method of treating a baseball bat made of wood, which consists in impregnating the outer layers of the bat barrel with a mixture containing casein glue, while preserving the handle portion and core of the bat in its natural condition.

2. A wooden baseball bat having the outer growth layers of the barrel portion impregnated with a mixture containing an adhesive, and having a relatively resilient barrel core, and handle portion.

In testimony whereof I afiix my signature.

HENRY CLAY HANNA. 

